Cocoa extracts as antioxidants

ABSTRACT

Disclosed and claimed are cocoa extracts such as polyphenols or procyanidins, methods for preparing such extracts, as well as uses for them, especially as antineoplastic agents and antioxidants. Disclosed and claimed are antineoplastic compositions containing cocoa polyphenols or procyanidins and methods for treating patients employing the compositions. Additionally disclosed and claimed is a kit for treating a patient in need of treatment with an antineoplastic agent containing cocoa polyphenols or procyanidins as well as a lyophilized antineoplastic composition containing cocoa polyphenols or procyanidins. Further, disclosed and claimed is the use of the invention in antioxidant, preservative and topoisomerase-inhibiting compositions and methods.

This application is a continuation of Ser. No. 10/790,268 filed Mar. 1,2004, now abandoned, which is a continuation of Ser. No. 10/342,772filed Jan. 15, 2003 now U.S. Pat. No. 6,790,966 issued Sep. 14, 2004,which is a continuation of Ser. No. 09/975,242 filed Oct. 11, 2001, nowU.S. Pat. 6,517,841 issued Feb. 11, 2003, which is a continuation ofSer. No. 09/768,473 filed Jan. 24, 2001 now U.S. Pat. 6,562,863 issuedMay 13, 2003, which is a continuation of Ser. No. 09/172,873 filed Oct.15, 1998 now U.S. Pat. No. 6,225,338 issued May 1, 2001, which is adivision of Ser. No. 08/839,446 filed Apr. 14, 1997 now U.S. Pat. No.5,891,905 issued Apr. 6, 1999, which is a division of Ser. No.08/687,885 filed Jul. 26, 1996 now U.S. Pat. No. 5,712,305 0issued Jan.27, 1998, which is a division of Ser. No. 08/317,226 filed Oct. 3, 1994now U.S. Pat. No. 5,554,645 issued Sep. 10, 1996.

The disclosures of Ser. No. 10/790,268 filed Mar. 1, 2004, of U.S. Pat.No. 6,790,966 issued Sep. 14, 2004, of U.S. Pat. No. 6,517,841 issuedFeb. 11, 2003, of U.S. Pat. No. 6,562,863 issued May 13, 2001, of U.S.Pat. No. 5,891,905 issued Apr. 6, 1999, of U.S. Pat. No. 5,712,305issued Jan. 27, 1998, and of U.S. Pat. No. 5,554,645 issued Sep. 10,1996 are incorporated herein by reference.

FIELD OF THE INVENTION

This invention relates to cocoa extracts such as polyphenols preferablypolyphenols enriched with procyanidins. This invention also relates tomethods for preparing such extracts, as well as to uses for them; forinstance, as antineoplastic agents and antioxidants.

Documents are cited in this disclosure with a full citation for eachappearing in a References section at the end of the specification,preceding the claims. These documents pertain to the field of thisinvention; and, each document cited herein is hereby incorporated hereinby reference.

BACKGROUND OF THE INVENTION

Polyphenols are an incredibly diverse group of compounds (Ferreira etal., 1992) which widely occur in a variety of plants, some of whichenter into the food chain. In some cases they represent an importantclass of compounds for the human diet. Although some of the polyphenolsare considered to be nonnutrative, interest in these compounds hasarisen because of their possible beneficial effects on health. Forinstance, quercitin (a flavonoid) has been shown to possessanticarcinogenic activity in experimental animal studies (Deshner etal., 1991 and Kato et al., 1983). (+)-Catechin and (−)-epicatechin(flavan-3-ols) have been shown to inhibit Leukemia virus reversetranscriptase activity (Chu et al., 1992). Nobotanin (an oligomerichydrolyzable tannin) has also been shown to possess anti-tumor activity(Okuda et al., 1992). Statistical reports have also shown that stomachcancer mortality is significantly lower in the tea producing districtsof Japan. Epigallocatechin gallate has been reported to be thepharmacologically active material in green tea that inhibits mouse skintumors (Okuda et al., 1992). Ellagic acid has also been shown to possessanticarcinogen activity in various animal tumor models (Bukharta et al.,1992). Lastly, proanthocyanidin oligomers have been patented by theKikkoman Corporation for use as antimutagens. Indeed, the area ofphenolic compounds in foods and their modulation of tumor development inexperimental animal models has been recently presented at the 202ndNational Meeting of The American Chemical society (Ho et al., 1992;Huang et al., 1992).

However, none of these reports teaches or suggests cocoa extracts, anymethods for preparing such extracts, or, any uses as antineoplasticagents for cocoa extracts.

Since unfermented cocoa beans contain substantial levels of polyphenols,the present inventors considered it possible that similar activities ofand uses for cocoa extracts, e.g., compounds within cocoa, could berevealed by extracting such compounds from cocoa and screening theextracts for activity. The National cancer Institute has screenedvarious Theobroma and Herrania species for anti-cancer activity as partof their massive natural product selection program. Low levels ofactivity were reported in some extracts of cocoa tissues, and the workwas not pursued. Thus, in the antineoplastic or anti-cancer art, cocoaand its extracts were not deemed to be useful; i.e., the teachings inthe antineoplastic or anti-cancer art lead the skilled artisan away fromemploying cocoa and its extracts as cancer therapy. Since a number ofanalytical procedures were developed to study the contributions of cocoapolyphenols to flavor development (Clapperton et al., 1992), the presentinventors decided to apply analogous methods to prepare samples foranti-cancer screening, contrary to the knowledge in the antineoplasticor anti-cancer art. Surprisingly, and contrary to the knowledge in theart, e.g., the National Cancer Institute screening, the presentinventors discovered that cocoa polyphenol extracts which containprocyanidins, have significant utility as anti-cancer or antineoplasticagents. Additionally, the inventors demonstrate that cocoa extractscontaining procyanidins have utility as antioxidants.

OBJECTS AND SUMMARY OF THE INVENTION

It is an object of the present invention to provide a method forproducing cocoa extract.

It is another object of the invention to provide a cocoa extract.

It is another object of the invention to provide an antioxidantcomposition.

It is another object of the invention to demonstrate inhibition of DNAtopoisomerase II enzyme activity.

It is yet another object of the present invention to provide a methodfor treating tumors or cancer.

It is still another object of the invention to provide an anti-cancer,anti-tumor or antineoplastic composition.

It is a further object of the invention to provide a method for makingan anti-cancer, anti-tumor or antineoplastic composition.

And, it is an object of the invention to provide a kit for use intreating tumors or cancer.

It has been surprisingly discovered that cocoa extract has anti-tumor,anti-cancer or antineoplastic activity; or, is an antioxidantcomposition or, inhibits DNA topoisomerase II enzyme activity.Accordingly, the present invention provides a substantially pure cocoaextract. The extract preferably comprises polyphenol(s) such aspolyphenol(s) enriched with cocoa procyanidin(s), such as polyphenols ofat least one cocoa procyanidin selected from (−) epicatechin,procyanidin B-2, procyanidin oligomers 2 through 12, preferably 2through 5 or 4 through 12, procyanidin B-5, procyanidin A-2 andprocyanidin C-1. The present invention also provides an anti-tumor,anti-cancer or antineoplastic or antioxidant or DNA topoisomerase IIinhibitor composition comprising a substantially pure cocoa extract orsynthetic cocoa polyphenol(s) such as polyphenol(s) enriched withprocyanidin(s) and a suitable carrier. The extract preferably comprisescocoa procyanidin(s). The cocoa extract is preferably obtained by aprocess comprising reducing cocoa beans to powder, defatting the powderand, extracting active compound(s) from the powder.

The present invention further comprehends a method for treating apatient in need of treatment with an anti-tumor, anti-cancer, orantineoplastic agent or an antioxidant or a DNA topoisomerase IIinhibitor comprising administering to the patient a compositioncomprising an effective quantity of a substantially pure cocoa extractor synthetic cocoa polyphenol(s) or procyanidin(s) and a carrier. Thecocoa extract can be cocoa procyanidin(s); and, is preferably obtainedby reducing cocoa beans to powder, defatting the powder and, extractingactive compounds(s) from the powder.

Additionally, the present invention provides a kit for treating apatient in need of treatment with an anti-tumor, anti-cancer, orantineoplastic agent or antioxidant or DNA topoisomerase II inhibitorcomprising a substantially pure cocoa extract or synthetic cocoapolyphenol(s) or procyanidin(s) and a suitable carrier for admixturewith the extract or synthetic polyphenol(s) or procyanidin(s).

These and other objects and embodiments are disclosed or will be obviousfrom the following Detailed Description.

BRIEF DESCRIPTION OF THE DRAWINGS

The following Detailed Description will be better understood byreference to the accompanying drawings wherein:

FIG. 1 shows a representative gel permeation chromatogram from thefractionation of crude cocoa procyanidins;

FIG. 2A shows a representative reverse-phase HPLC chromatogram showingthe separation (elution profile) of cocoa procyanidins extracted fromunfermented cocoa;

FIG. 2B shows a representative normal phase HPLC separation of cocoaprocyanidins extracted from unfermented cocoa;

FIG. 3 shows several representative procyanidin structures;

FIGS. 4A-4E show representative HPLC chromatograms of five fractionsemployed in screening for anti-cancer or antineoplastic activity;

FIGS. 5 and 6A-6D show the dose-response relationship between cocoaextracts and cancer cells ACHN (FIG. 5) and PC-3 (FIGS. 6A-6D)(fractional survival vs. dose, μg/ml); M&M2 F4/92, M&MA+E U12P1, M&MB+EY192P1, M&MC+E U12P2, M&MD+E U12P2;

FIGS. 7A to 7H show the typical dose response relationships betweencocoa procyanidin fractions A, B, C, D, E, A+B, A+E, and A+D, and thePC-3 cell line (fractional survival vs. dose, μg/ml); MM-1A 0212P3, MM-1B 0162P1, MM-1 C 0122P3, MM-1 D 0122P3, MM-1 E 0292P8, MM-1 A/B 0292P6,MM-1 A/E 0292P6, MM-1 A/D 0292P6;

FIGS. 8A to 8H show the typical dose response relationships betweencocoa procyanidin fractions A, B, C, D, E, A+B, B+E, and D+E and the KBNasopharyngeal/HeLa cell line (fractional survival vs. dose, μg/ml);MM-1AO92K3, MM-1 B 0212K5, MM-1 C 0162K3, MM-1 D O212K5, MM-1 B 0292K5,MM-1 A/B O292K3, MM-1 B/E 0292K4, MM-1 D/E 0292K5;

FIGS. 9A to 9H show the typical dose response relationship between cocoaprocyanidin fractions A, B, C, D, E, B+D, A+E and D+E and the HCT-116cell line (fractional survival vs. dose, μg/ml); MM-1 C 0192H5, D0192H5, E 0192H5, MM-1 B&D 0262H2, A/E 0262H3, MM-1 D&E 0262H1;

FIGS. 10A to 10H show typical dose response relationships between cocoaprocyanidin fractions A, B, C, D, A, B+D, C+D and A+E and the ACHN renalcell line (fractional survival vs. dose, μg/ml); MM-1 A 092A5, MM-1 B092A5, MM-1 C 0192A7, MM-1 D 0192A7, M&M1 E 0192A7, MM-1 B&D 0302A6,MM-1 C&D 0302A6, MM-1 A&E 0262A6;

FIGS. 11A to 11H show typical dose response relationships between cocoaprocyanidin fractions A, B, C, D, E, A+E, B+E and C+E and the A-549 lungcell line (fractional survival vs. dose, g/ml); MM-1 A 019258, MM-1 B09256, MM-1 C 019259, MM-1 D 019258, MM-1 E 019258, A/E 026254, MM-1 B&E030255, MM-1 C&E N6255;

FIGS. 12A to 12H show typical dose response relationships between cocoaprocyanidin fractions A, B, C, D, E, B+C, C+D and D+E and the SK-5melanoma cell line (fractional survival vs. dose μg/ml); MM-1 A 0212S4,MM-1 B 0212S4, MM-1 C 0212S4, MM-1 D 0212S4, MM-1 E N32S1, MM-1 B&CN32S2, MM-1 C&D N32S3, MM-1 D&E N32S3;

FIGS. 13A to 13H show typical dose response relationships between cocoaprocyanidin fractions A, B, C, D, E, B+C, C+E, and D+E and the MCF-7breast cell line (fractional survival vs. dose, μg/ml); MM-1 A N22M4,MM-1 B N22M4, MM-1 C N22M4, MM-1 D N22M3, MM-1 E 0302M2, MM-1 B/C0302M4, MM-1 C&E N22M3, MM-1 D&E N22M3;

FIG. 14 shows typical dose response relationships for cocoa procyanidin(particularly fraction D) and the CCRF-CEM T-cell leukemia cell line(cells/ml vs. days of growth; open circle is control, darkened circle is125 μg fraction D, open inverted triangle is 250 μg fraction D, darkenedinverted triangle is 500 μg fraction D);

FIG. 15 A shows a comparison of the XTT and Crystal Violet cytotoxicityassays against MCF-7 p168 breast cancer cells treated with fraction D+E(open circle is XTT and darkened circle is Crystal Violet);

FIG. 15 B shows a typical dose response curve obtained from MDA MB231breast cell line treated with varying levels of crude polyphenolsobtained from UIT-1 cocoa genotype (absorbance (540 nm) vs. Days; opencircle is control, darkened circle is vehicle, open inverted triangle is250 μg/ml, darkened inverted triangle is 100 μg/ml, open square is 10μg/ml; absorbance of 2.0 is maximum of plate reader and may not benecessarily representative of cell number);

FIG. 15 C shows a typical dose response curve obtained from PC-3prostate cancer cell line treated with varying levels of crudepolyphenols obtained from UIT-1 cocoa genotype (absorbance (540 nm) vs.Days; open circle is control, darkened circle is vehicle, open invertedtriangle is 250 μg/ml, darkened inverted triangle is 100 μg/ml and opensquare is 10 μg/ml);

FIG. 15 D shows a typical dose-response curve obtained from MCF-7 p168breast cancer cell line treated with varying levels of crude polyphenolsobtained from UIT-1 cocoa genotype (absorbance (540 nm) vs. Days; opencircle is control, darkened circle is vehicle, open inverted triangle is250 μg/ml, darkened inverted triangle is 100 μg/ml, open square is 10μg/ml, darkened square is 1 μg/ml; absorbance of 2.0 is maximum of platereader and may not be necessarily representative of cell number);

FIG. 15 E shows a typical dose response curve obtained from Helacervical cancer cell line treated with varying levels of crudepolyphenols obtained from UIT-1 cocoa genotype (absorbance (540 nm) vs.Days; open circle is control, darkened circle is vehicle, open invertedtriangle is 250 μg/ml, darkened inverted triangle is 100 μg/ml, opensquare is 10 μg/ml; absorbance of 2.0 is maximum of plate reader and maynot be necessarily representative of cell number);

FIG. 15 F shows cytotoxic effects against Hela cervical cancer cell linetreated with different cocoa polyphenol fractions (absorbance (540 nm)vs. Days; open circle is 100 μg/ml fractions A-E, darkened circle is 100μg/ml fractions A-C, open inverted triangle is 100 μg/ml fractions D&E;absorbance of 2.0 is maximum of plate reader and not representative ofcell number);

FIG. 15 G shows cytotoxic effects at 100 μl/ml against SKBR-3 breastcancer cell line treated with different cocoa polyphenol fractions(absorbance (540 nm) vs. Days; open circle is fractions A-E, darkenedcircle is fractions A-C, open inverted triangle is fractions D&E);

FIG. 15 H shows typical dose-response relationships between cocoaprocyanidin fraction D+E on Hela cells (absorbance (540 nm) vs. Days;open circle is control, darkened circle is 100 μg/ml, open invertedtriangle is 75 μg/ml, darkened inverted triangle is 50 μg/ml, opensquare is 25 μg/ml, darkened square is 10 μg/ml; absorbance of 2.0 ismaximum of plate reader and is not representative of cell number);

FIG. 15 I shows typical dose-response relationship between cocoaprocyanidin fraction D+E on SKBR-3 cells (absorbance (540 nm) vs. Days;open circle is control, darkened circle is 100 μg/1 ml, open invertedtriangle is 75 μg/ml, darkened inverted triangle is 50 μg/ml, opensquare is 25 μg/ml, darkened square is 10 μg/ml);

FIG. 15 J shows typical dose-response relationships between cocoaprocyanidin fraction D+E on Hela cells using the Soft Agar Cloning assay(bar chart; number of colonies vs. control, 1, 10, 50, and 100 μg/ml);

FIG. 15 K shows the growth inhibition of Hela cells when treated withcrude polyphenol extracts obtained from eight different cocoa genotypes(% control vs. concentration, μg/ml; open circle is C-1, darkened circleis C-2, open inverted triangle is C-3, darkened inverted triangle isC-4, open square is C-5, darkened square is C-6, open triangle is C-7,darkened triangle is C-8; C-1=UF-12: horti race=Criollo and descriptionis crude extracts of UF-12 (Brazil) cocoa polyphenols(decaffeinated/detheobrominated); C-2=NA-33: horti race=Forastero anddescription is crude extracts of NA-33 (Brazil) cocoa polyphenols(decaffeinated/detheobrominated); C-3=EEG-48: horti race=Forastero anddescription is crude extracts of EEG-48 (Brazil) cocoa polyphenols(decaffeinated/detheobrominated); C-4=unknown: horti race=Forastero anddescription is crude extracts of unknown (W. African) cocoa polyphenols(decaffeinated/detheobrominated); C-5=UF-613: horti race=Trinitario anddescription is crude extracts of UF-613 (Brazil) cocoa polyphenols(decaffeinated/detheobrominated); C-6=ICS-100: horti race=Trinitario anddescription is crude extracts of ICS-100 (Brazil) cocoa polyphenols(decaffeinated/detheobrominated); C-7=ICS-139: horti race=Trinitario anddescription is crude extracts of ICS-139 (Brazil) cocoa polyphenols(decaffeinated/detheobrominated); C-8=UIT-1: horti race=Trinitario anddescription is crude extracts of UIT-1 (Malaysia) cocoa polyphenols(decaffeinated/detheobrominated));

FIG. 15 L shows the growth inhibition of Hela cells when treated withcrude polyphenol extracts obtained from fermented cocoa beans and driedcocoa beans (stages throughout fermentation and sun drying; % controlvs. concentration, μg/ml; open circle is day zero fraction, darkenedcircle is day 1 fraction, open inverted triangle is day 2 fraction,darkened inverted triangle is day 3 fraction, open square is day 4fraction and darkened square is day 9 fraction);

FIG. 15 M shows the effect of enzymically oxidized cocoa procyanidinsagainst Hela cells (dose response for polyphenol oxidase treated crudecocoa polyphenol; % control vs. concentration, μg/ml; darkened square iscrude UIT-1 (with caffeine and theobromine), open circle crude UIT-1(without caffeine and theobromine) and darkened circle is crude UIT-1(polyphenol oxidase catalyzed));

FIG. 15 N shows a representative semi-preparative reverse phase HPLCseparation for combined cocoa procyanidin fractions D and E;

FIG. 15 O shows a representative normal phase semi-preparative HPLCseparation of a crude cocoa polyphenol extract;

FIG. 16 shows typical Rancimat Oxidation curves for cocoa procyanidinextract and fractions in comparison to the synthetic antioxidants BHAand BHT (arbitrary units vs. time; dotted line and cross (+) is BHA andBHT; * is D-E; x is crude; open square is A-C; and open diamond iscontrol);

FIG. 17 shows a typical Agarose Gel indicating inhibition oftopoisomerase II catalyzed decatenation of kinetoplast DNA by cocoaprocyanidin fractions (Lane 1 contains 0.5 μg of marker (M)monomer-length kinetoplast DNA circles; Lanes 2 and 20 containkinetoplast DNA that was incubated with Topoisomerase II in the presenceof 4% DMSO, but in the absence of any cocoa procyanidins. (Control-C);Lanes 3 and 4 contain kinetoplast DNA that was incubated withTopoisomerase II in the presence of 0.5 and 5.0 μg/mL cocoa procyanidinfraction A; Lanes 5 and 6 contain kinetoplast DNA that was incubatedwith Topoisomerase II in the presence of 0.5 and 5.0 μg/mL cocoaprocyanidin fraction B; Lanes 7, 8, 9, 13, 14 and 15 are replicates ofkinetoplast DNA that was incubated with Topoisomerase II in the presenceof 0.05, 0.5 and 5.0 μg/mL cocoa procyanidin fraction D; Lanes 10, 11,12, 16, 17 and 18 are replicates of kinetoplast DNA that was incubatedwith Topoisomerase II in the presence of 0.05, 0.5, and 5.0 μg/mL cocoaprocyanidin fraction E; Lane 19 is a replicate of kinetoplast DNA thatwas incubated with Topoisomerase II in the presence of 5.0 μg/mL cocoaprocyanidin fraction E);

FIG. 18 shows dose response relationships of cocoa procyanidin fractionD against DNA repair competent and deficient cell lines (fractionalsurvival vs. μg/ml; left side xrs-6 DNA Deficient Repair Cell Line, MM-1D D282X1; right side BR1 competent DNA Repair Cell Line, MM-1 D D282B1);

FIG. 19 shows the dose-response curves for Adriamycin resistant MCF-7cells in comparison to a MCF-7 p168 parental cell line when treated withcocoa fraction D+E (t control vs. concentration, μg/ml; open circle isMCF-7 p168; darkened circle is MCF-7 ADR); and

FIG. 20 shows the dose-response effects on Hela cells when treated at100 μg/mL and 25 μg/mL levels of twelve fractions prepared by Normalphase semi-preparative HPLC (bar chart, % control vs. control andfractions 1-12).

DETAILED DESCRIPTION

As discussed above, it has now been surprisingly found that cocoaextracts exhibit anti-cancer, anti-tumor or antineoplastic activity,antioxidant activity and, inhibit DNA topoisomerase II enzyme. Theextracts are generally prepared by reducing cocoa beans to a powder,defatting the powder, and extracting the active compound(s) from thedefatted powder. The powder can be prepared by freeze-drying the cocoabeans and pulp, depulping the cocoa beans and pulp, dehulling thefreeze-dried cocoa beans, and grinding the dehulled beans. Theextraction of active compounds can be by solvent extraction techniques.The extracts can be purified; for instance, by gel permeationchromatography or by preparative High Performance Liquid Chromatography(HPLC) techniques or by a combination of such techniques. The extractshaving activity, without wishing to necessarily be bound by anyparticular theory, have been identified as cocoa polyphenol(s) such asprocyanidins. These cocoa procyanidins have significant anti-cancer,anti-tumor or antineoplastic activity; antioxidant activity; and inhibitDNA topoisomerase II enzyme.

Anti-cancer, anti-tumor or antineoplastic or, antioxidant or DNAtopoisomerase II enzyme inhibiting compositions containing the inventivecocoa polyphenols or procyanidins can be prepared in accordance withstandard techniques well known to those skilled in the pharmaceuticalart. Such compositions can be administered to a patient in need of suchadministration in dosages and by techniques well known to those skilledin the medical arts taking into consideration such factors as the age,sex, weight, and condition of the particular patient, and the route ofadministration. The compositions can be co-administered or sequentiallyadministered with other antineoplastic, anti-tumor or anti-cancer agentsor antioxidant or DNA topoisomerase II enzyme inhibiting agents and/orwith agents which reduce or alleviate ill effects of antineoplastic,anti-tumor or anti-cancer agents or antioxidant or DNA topoisomerase IIenzyme inhibiting agents; again, taking into consideration such factorsas the age, sex, weight, and condition of the particular patient, and,the route of administration.

Examples of compositions of the invention include solid compositions fororal administration such as capsules, tablets, pills and the like, aswell as chewable solid formulations, to which the present invention maybe well-suited since it is from an edible source (e.g., cocoa orchocolate flavored solid compositions); liquid preparations for orifice,e.g., oral, nasal, anal, vaginal etc., administration such assuspensions, syrups or elixirs; and, preparations for parental,subcutaneous, intradermal, intramuscular or intravenous administration(e.g., injectable administration) such as sterile suspensions oremulsions. However, the active ingredient in the compositions maycomplex with proteins such that when administered into the bloodstream,clotting may occur due to precipitation of blood proteins; and, theskilled artisan should take this into account. In such compositions theactive cocoa extract may be in admixture with a suitable carrier,diluent, or excipient such as sterile water, physiological saline,glucose or the like. The active cocoa extract of the invention can beprovided in lyophilized form for reconstituting, for instance, inisotonic aqueous, saline buffer.

Further, the invention also comprehends a kit wherein the active cocoaextract is provided. The kit can include a separate container containinga suitable carrier, diluent or excipient. The kit can also include anadditional anti-cancer, anti-tumor or antineoplastic agent orantioxidant or DNA topoisomerase II enzyme inhibiting agent and/or anagent which reduces or alleviates ill effects of antineoplastic,anti-tumor or anti-cancer agents or antioxidant or DNA topoisomerase IIenzyme inhibiting agents for co- or sequential-administration. Theadditional agent(s) can be provided in separate container(s) or inadmixture with the active cocoa extract. Additionally, the kit caninclude instructions for mixing or combining ingredients and/oradministration.

Furthermore, while the invention is described with respect to cocoaextracts preferably comprising cocoa procyanidins, from this disclosurethe skilled organic chemist will appreciate and envision syntheticroutes to obtain the active compounds. Accordingly, the inventioncomprehends synthetic cocoa polyphenols or procyanidins or theirderivatives which include, but are not limited to glycosides, gallates,esters, etc. and the like.

The following non-limiting Examples are given by way of illustrationonly and are not to be considered a limitation of this invention, manyapparent variations of which are possible without departing from thespirit or scope thereof.

EXAMPLES Example 1 Cocoa Source and Method of Preparation

Several Theobroma cacao genotypes which represent the three recognizedhorticultural races of cocoa (Enriquez, 1967; Engels, 1981) wereobtained from the three major cocoa producing origins of the world. Alist of those genotypes used in this study are shown in Table 1.Harvested cocoa pods were opened and the beans with pulp were removedfor freeze drying. The pulp was manually removed from the freeze driedmass and the beans were subjected to analysis as follows. Theunfermented, freeze dried cocoa beans were first manually dehulled, andground to a fine powdery mass with a TEKMAR Mill. The resultant mass wasthen defatted overnight by Soxhlet extraction using redistilled hexaneas the solvent. Residual solvent was removed from the defatted mass byvacuum at ambient temperature.

TABLE 1 Description of Theobroma cacao Source Material GENOTYPE ORIGINHORTICULTURAL RACE UIT-1 Malaysia Trinitario Unknown West AfricaForastera ICS-100 Brazil Trinitario ICS-39 Brazil Trinitario UF-613Brazil Trinitario EEG-48 Brazil Forastero UF-12 Brazil Criollo NA-33Brazil Forastero

Example 2 Procyanidin Extraction Procedures

A. Method 1

Procyanidins were extracted from the defatted, unfermented, freeze driedcocoa beans of Example 1 using a modification of the method described byJalal and Collin (1977) Procyanidins were extracted from 50 gram batchesof the defatted cocoa mass with 2×400 mL 70% acetone/deionized waterfollowed by 400 mL 70% methanol/deionized water. The extracts werepooled and the solvents removed by evaporation at 45° C. with a rotaryevaporator held under partial vacuum. The resultant aqueous phase wasdiluted to 1 L with deionized water and extracted 2× with 400 mL CHCl₃.The solvent phase was discarded. The aqueous phase was then extracted 4×with 500 mL ethyl acetate. Any resultant emulsions were broken bycentrifugation on a Sorvall RC 28S centrifuge operated at 2,000×g for 30min. at 10° C. To the combined ethyl acetate extracts, 100-200 mLdeionized water was added. The solvent was removed by evaporation at 45°C. with a rotary evaporator held under partial vacuum. The resultantaqueous phase was frozen in liquid N₂ followed by freeze drying on aLABCONCO Freeze Dry System. The yields of crude procyanidins that wereobtained from the different cocoa genotypes are listed in Table 2.

TABLE 2 Crude Procyanidin Yields GENOTYPE ORIGIN YIELDS (g) UIT-1Malaysia 3.81 Unknown West Africa 2.55 ICS-100 Brazil 3.42 ICS-39 Brazil3.45 UF-613 Brazil 2.98 EEG-48 Brazil 3.15 UF-12 Brazil 1.21 NA-33Brazil 2.23B. Method 2

Alternatively, procyanidins are extracted from defatted, unfermented,freeze dried cocoa beans of Example 1 with 70% aqueous acetone. Tengrams of defatted material was slurried with 100 mL solvent for 5-10min. The slurry was centrifuged for 15 min. at 4° C. at 3000×g and thesupernatant passed through glass wool. The filtrate was subjected todistillation under partial vacuum and the resultant aqueous phase frozenin liquid N₂, followed by freeze drying on a LABCONCO Freeze Dry system.The yields of crude procyanidins ranged from 15-20%.

Without wishing to be bound by any particular theory, it is believedthat the differences in crude yields reflected variations encounteredwith different genotypes, geographical origin, horticultural race, andmethod of preparation.

Example 3 Partial Purification of Cocoa Procyanidins

A. Gel Permeation Chromatography

Procyanidins obtained from Example 2 were partially purified by liquidchromatography on Sephadex LH-20 (28×2.5 cm). Separations were aided bya step gradient into deionized water. The initial gradient compositionstarted with 15% methanol in deionized water which was followed stepwise every 30 min. with 25% methanol in deionized water, 35% methanol indeionized water, 70% methanol in deionized water, and finally 100%methanol. The effluent following the elution of the xanthine alkaloids(caffeine and theobromine) was collected as a single fraction. Thefraction yielded a xanthine alkaloid free subtraction which wassubmitted to further subfractionation to yield five subtractionsdesignated MM2A through MM2E. The solvent was removed from eachsubtraction by evaporation at 45° C. with a rotary evaporator held underpartial vacuum. The resultant aqueous phase was frozen in liquid N₂ andfreeze dried overnight on a LABCONCO Freeze Dry System. A representativegel permeation chromatogram showing the fractionation is shown inFIG. 1. Approximately, 100 mg of material was subfractionated in thismanner.

FIG. 1: Gel Permeation Chromatogram of Crude Procyanidins on SephadexLH-20

Chromatographic Conditions Column; 28×2.5 cm Sephadex LH-20, MobilePhase: Methanol/Water Step Gradient, 15:85, 25:75, 35:65, 70:30, 100:0Stepped at ½ Hour Intervals, Flow Rate; 1.5 ml/min, Detector; UV @λ₁=254 nm and λ₂=365 nm, Chart Speed: 0.5 mm/min, Column Load; 120 mg.

B. Semi-Preparative High Performance Liquid Chromatography—(HPLC)

Method 1: Reverse Phase Separation

Procyanidins obtained from Example 2 and/or 3A were partially purifiedby semi-preparative HPLC. A Hewlett Packard 1050 HPLC System equippedwith a variable wavelength detector, Rheodyne 7010 injection valve with1 mL injection loop was assembled with a Pharmacia FRAC-100 FractionCollector. Separations were effected on a Phenomenex Ultracarb 10 μ ODScolumn (250×22.5 mm) connected with a Phenomenex 10 μ ODS Ultracarb(60×10 mm) guard column. The mobile phase composition was A=water;B=methanol used under the following linear gradient conditions: [Time, %A]; (0, 85), (60, 50), (90, 0), and (110, 0) at a flow rate of 5 mL/min.

A representative Semi-preparative HPLC trace is shown in FIG. 15N forthe separation of procyanidins present in fraction D+E. Individual peaksor select chromatographic regions were collected on timed intervals ormanually by fraction collection for further purification and subsequentevaluation. Injection loads ranged from 25-100 mg of material.

Method 2. Normal Phase Separation

Procyanidin extracts obtained from Examples 2 and/or 3A were partiallypurified by semi-preparative HPLC. A Hewlett Packard 1050 HPLC system,Millipore-waters Model 480 LC detector set at 254 nm was assembled witha Pharmacia Frac-100 Fraction Collector set in peak mode. Separationswere effected on a Supelco 5 μ Supelcosil LC-Si column (250×10 mm)connected with a Supelco 5 μ Supelguard LC-Si guard column (20×4.6 mm).Procyanidins were eluted by a linear gradient under the followingconditions: (Time, % A, % B); (0, 82, 14), (30, 67.6, 28.4), (60, 46,50), (65, 10, 86), (70, 10, 86) followed by a 10 min. re-equilibration.Mobile phase composition was A=dichloromethane; B=methanol; and C=aceticacid:water (1:1). A flow rate of 3 mL/min was used. Components weredetected by UV at 254 nm, and recorded on a Kipp & Zonan BD41 recorder.Injection volumes ranged from 100-250 μL of 10 mg of procyanidinextracts dissolved in 0.25 mL 70% aqueous acetone. A representativesemi-preparative HPLC trace is shown in FIG. 15 O. Individual peaks orselect chromatographic regions were collected on timed intervals ormanually by fraction collection for further purification and subsequentevaluation.

HPLC Conditions: 250 × 10 mm Supelco supelcosil LC-Si (5 μm)Semipreparative Column 20 × 4.6 mm Supelco Supelcosil LC-Si (5 μm) GuardColumn Detector: Waters LC Spectrophotometer Model 480 @ 254 nm Flowrate: 3 mL/min, Column Temperature: ambient, Injection: 250 μL of 70%aqueous acetone extract. Gradient: Acetic Time (min) CH₂Cl₂ MethanolAcid/H₂0 (1:1)  0 82 14 4 30 67.6 28.4 4 60 46 50 4 65 10 86 4 70 10 864

The fractions obtained were as follows:

FRACTION TYPE 1 dimers 2 trimers 3 tetramers 4 pentamers 5 hexamers 6heptamers 7 octamers 8 nonamers 9 decamers 10 undecamers 11 dodecamers12 higher oligomers

Example 4 Analytical HPLC Analysis of Procyanidin Extracts

Method 1: Reverse Phase Separation

Procyanidin extracts obtained from Example 3 were filtered through a0.45 μ filter and analyzed by a Hewlett Packard 1090 ternary HPLC systemequipped with a Diode Array detector and a HP model 1046A ProgrammableFluorescence Detector. Separations were effected at 45° C. on aHewlett-Packard 5 μ Hypersil ODS column (200×2.1 mm). The flavanols andprocyanidins were eluted with a linear gradient of 60% B into A followedby a column wash with B at a flow rate of 0.3 mL/min. The mobile phasecomposition was B=0.5% acetic acid in methanol and A=0.5% acetic acid indeionized water. Acetic acid levels in A and B mobile phases can beincreased to 2%. Components were detected by fluorescence, whereλ_(ex)=276 nm and λ_(em)=316 nm. Concentrations of (+)-catechin and(−)-epicatechin were determined relative to reference standardsolutions. Procyanidin levels were estimated by using the responsefactor for (−)-epicatechin. A representative HPLC chromatogram showingthe separation of the various components is shown in FIG. 2A for onecocoa genotype. Similar HPLC profiles were obtained from the other cocoagenotypes.

HPLC Conditions: Column: 200 × 2.1 mm Hewlett Packard Hypersil ODS (5μ)Guard column: 20 × 2.1 mm Hewlett Packard Hypersil ODS (5μ) Detectors:Diode Array @ 289 nm; Fluorescence λ_(ex) = 276 nm; λ_(em) = 316 nm.Flow rate: 3 mL/min. Column Temperature: 45° C. Gradient: 0.5% AceticAcid 0.5% Acetic acid Time (min) in deionized water in methanol  0 100 050 40 60 60 0 100

Method 2: Normal Phase Separation

Procyanidin extracts obtained from Examples 2 and/or 3 were filteredthrough a 0.45 μ filter and analyzed by a Hewlett Packard 1090 Series IIHPLC system equipped with a HP model 1046A Programmable Fluorescencedetector and Diode Array detector. Separations were effected at 37° C.on a 5 μ Phenomenex Lichrosphere Silica 100 column (250×3.2 mm)connected to a Supelco Supelguard LC-Si 5 μ guard column (20×4.6 mm).Procyanidins were eluted by linear gradient under the followingconditions: (Time, % A, % B); (0, 82, 14), (30, 67.6, 28.4), (60, 46,50), (65, 10, 86), (70, 10, 86) followed by an 8 min. re-equilibration.Mobile phase composition was A=dichloromethane, B=methanol, and C=aceticacid:water at a volume ratio of 1:1. A flow rate of 0.5 mL/min. wasused. Components were detected by fluorescence, where λ_(ex)=276 nm andλ_(em)=316 nm or by UV at 280 nm. A representative HPLC chromatogramshowing the separation of the various procyanidins is shown in FIG. 2Bfor one genotype. Similar HPLC profiles were obtained from other cocoagenotypes.

HPLC Conditions: 250 × 3.2 mm Phenomenex Lichrosphere Silica 100 column(5μ) 20 × 4.6 mm Supelco Supelguard LC-Si (5μ) guard column Detectors:Photodiode Array @ 280 nm Fluorescence λ_(ex) = 276 nm; λ_(em) = 316 nm.Flow rate: 0.5 mL/min. Column Temperature: 37° C. Acetic Gradient:Acid/Water Time (min.) CH₂—Cl₂ Methanol (1:1)  0 82 14 4 30 67.6 28.4 460 46 50 4 65 10 86 4 70 10 86 4

Example 5 Identification of Procyanidins

Procyanidins were purified by liquid chromatography on Sephadex LH-20(28×2.5 cm) columns followed by semi-preparative HPLC using a 10 μμBondapak C18 (100×8 mm) column or by semi-preparative HPLC using a 5 μSupelcosil LC-Si (250×10 mm) column.

Partially purified isolates were analyzed by Fast Atom Bombardment-MassSpectrometry (FAB-MS) on a VG ZAB-T high resolution MS system using aLiquid secondary Ion Mass Spectrometry (LSIMS) technique in positive andnegative ion modes. A cesium ion gun was used as the ionizing source at30 kV and a “Magic Bullet Matrix” (1:1 dithiothreitol/dithioerythritol)was used as the proton donor.

Analytical investigations of these fractions by LSIMS revealed thepresence of a number of flavan-3-ol oligomers as shown in Table 3.

TABLE 3 LSIMS (Positive Ion) Data from Cocoa Procyanidin Fractions (M +1)⁺ (M + Na)⁺ Oligomer m/z m/z Mol. Wt. Monomers  291  313  290(catechins) Dimer(s) 577/579 599/601 576/578 Trimer(s) 865/867 887/889884/866 Tetramer(s) 1155 1177 1154 Pentamer(s) 1443 1465 1442 Hexamer(s)1731 1753 1730 Heptamer(s) — 2041 2018 Octamer(s) — 2329 2306 Nonamer(s)— 2617 2594 Decamer(s) — 2905 2882 Undecamer(s) — — 3170 Dodecamer(s) —— 3458

The major mass fragment ions were consistent with work previouslyreported for both positive and negative ion FAB-MS analysis ofprocyanidins (Self et al., 1986 and Porter et al., 1991). The ioncorresponding to m/z 577 (M+H)⁺ and its sodium adduct at m/z 599 (M+Na)⁺suggested the presence of doubly linked procyanidin dimers in theisolates. It was interesting to note that the higher oligomers were morelikely to form sodium adducts (M+Na)⁺ than their protonated molecularions (M+H)⁺. The procyanidin isomers B-2, B-5 and C-1 were tentativelyidentified based on the work reported by Revilla et al. (1991), Self etal. (1986) and Porter et al. (1991). Procyanidins up to both the octamerand decamer were verified by FAB-MS in the partially purified fractions.Additionally, evidence for procyanidins up to the dodecamer wereobserved from normal phase HPLC analysis (see FIG. 2B). Without wishingto be bound by any particular theory, it is believed that the dodecameris the limit of solubility in the solvents used in the extraction andpurification schemes. Table 4 lists the relative concentrations of theprocyanidins found in xanthine alkaloid free isolates based on reversephase HPLC analysis. Table 5 lists the relative concentrations of theprocyanidins based on normal phase HPLC analysis.

TABLE 4 Relative Concentrations of Procyanidins in the Xanthine AlkaloidFree Isolates Component Molecular Weight Amount (+)-catechin 290 1.6%(−)-epicatechin 290 38.2% B-2 Dimer 578 11.0% B-5 Dimer 578 5.3% C-1Trimer 666 9.3% Doubly linked dimers 576 3.0% Tetramer(s) 1154  4.5%Pentamer-Octamer 1442-2306 24.5% Unknowns and higher — 2.6% oligomers

TABLE 5 Relative Concentrations of Procyanidins in Aqueous AcetoneExtracts Component Molecular Weight Amount (+)-catechin and 290 (samefor each) 41.9% (−)-epicatechin B-2 and B-5 Dimers  578 13.9% Trimers884/866 11.3% Tetramers 1154 9.9% Pentamers 1442 7.8% Hexamers 1730 5.1%Heptamers 2018 4.2% Octamers 2306 2.8% Nonamers 2594 1.6% Decamers 28820.7% Undecamers 3170 0.2% Dodecamers 3458 <0.1%

FIG. 3 shows several procyanidin structures and FIGS. 4A-4E show therepresentative HPLC chromatograms of the five fractions employed in thefollowing screening for anti-cancer or antineoplastic activity. The HPLCconditions for FIGS. 4A-4E were as follows:

-   -   HPLC Conditions: Hewlett Packard 1090 ternary HPLC System        equipped with HP Model 1046A Programmable Fluorescence Detector.    -   Column: Hewlett Packard 5 μ Hypersil ODS (200×2.1 mm) Linear        Gradient of 60% B into A at a flow rate of 0.3 ml/min. B=0.5%        acetic acid in methanol; A=0.5% acetic acid in deionized water.        λ_(ex)=280 nm; λ_(em)=316 nm.

FIG. 15 O shows a representative semi-prep HPLC chromatogram of anadditional 12 fractions employed in the screening for anticancer orantineoplastic activity (HPLC conditions stated above).

Example 6 Anti-cancer, Anti-tumor or Antineoplastic Activity of CocoaExtracts (Procyanidins)

The MTT (3-[4,5-dimethyl thiazol-2yl]-2,5-diphenyltetrazoliumbromide)-microtiter plate tetrazolium cytotoxicity assay originallydeveloped by Mosmann (1983) was used to screen test samples from Example5. Test samples, standards (cisplatin and chlorambucil) and MTT reagentwere dissolved in 100% DMSO (dimethyl sulfoxide) at a 10 mg/mLconcentration. Serial dilutions were prepared from the stock solutions.In the case of the test samples, dilutions ranging from 0.01 through 100μg/mL were prepared in 0.5% DMSO.

All human tumor cell lines were obtained from the American Type CultureCollection. Cells were grown as mono layers in alpha-MEM containing 10%fetal bovine serum, 100 units/mL penicillin, 100 μg/mL streptomycin and240 units/mL nystatin. The cells were maintained in a humidified, 5% CO₂atmosphere at 37° C.

After trypsinization, the cells are counted and adjusted to aconcentration of 50×10⁵ cells/mL (varied according to cancer cell line).200 μL of the cell suspension was plated into wells of 4 rows of a96-well microtiter plate. After the cells were allowed to attach forfour hours, 2 μL of DMSO containing test sample solutions were added toquadruplicate wells. Initial dose-response finding experiments, usingorder of magnitude test sample dilutions were used to determine therange of doses to be examined. Well absorbencies at 540 nm were thenmeasured on a BIO RAD MP450 plate reader. The mean absorbance ofquadruplicate test sample treated wells was compared to the control, andthe results expressed as the percentage of control absorbance plus/minusthe standard deviation. The reduction of MTT to a purple formazanproduct correlates in a linear manner with the number of living cells inthe well. Thus, by measuring the absorbance of the reduction product, aquantitation of the percent of cell survival at a given dose of testsample can be obtained. Control wells contained a final concentration of1% DMSO.

Two of the samples were first tested by this protocol. Sample MM1represented a very crude isolate of cocoa procyanidins and containedappreciable quantities of caffeine and theobromine. Sample MM2represented a cocoa procyanidin isolate partially purified by gelpermeation chromatography. Caffeine and theobromine were absent in MM2.Both samples were screened for activity against the following cancercell lines using the procedures previously described:

-   -   HCT 116 colon cancer    -   ACHN renal adenocarcinoma    -   SK-5 melanoma    -   A498 renal adenocarcinoma    -   MCF-7 breast cancer    -   PC-3 prostate cancer    -   CAPAN-2 pancreatic cancer

Little or no activity was observed with MM1 on any of the cancer celllines investigated. MM2 was found to have activity against HCT-116, PC-3and ACHN cancer cell lines. However, both MM1 and MM2 were found tointerfere with MTT such that it obscured the decrease in absorbance thatwould have reflected a decrease in viable cell number. This interferencealso contributed to large error bars, because the chemical reactionappeared to go more quickly in the wells along the perimeter of theplate. A typical example of these effects is shown in FIG. 5. At thehigh concentrations of test material, one would have expected to observea large decrease in survivors rather than the high survivor levelsshown. Nevertheless, microscopic examinations revealed that cytotoxiceffects occurred, despite the MTT interference effects. For instance, anIC₅₀ value of 0.5 μg/mL for the effect of MM2 on the ACHN cell line wasobtained in this manner.

These preliminary results, in the inventors' view, required amendment ofthe assay procedures to preclude the interference with MTT. This wasaccomplished as follows. After incubation of the plates at 37° C. in ahumidified, 5% CO₂ atmosphere for 18 hours, the medium was carefullyaspirated and replaced with fresh alpha-MEM media. This media was againaspirated from the wells on the third day of the assay and replaced with100 μL of freshly prepared McCoy's medium. 11 μL of a 5 mg/mL stocksolution of MTT in PBS (Phosphate Buffered Saline) were then added tothe wells of each plate. After incubation for 4 hours in a humidified,5% CO₂ atmosphere at 37° C., 100 μL of 0.04 N HCl in isopropanol wasadded to all wells of the plate, followed by thorough mixing tosolubilize the formazan produced by any viable cells. Additionally, itwas decided to subfractionate the procyanidins to determine the specificcomponents responsible for activity.

The subfractionation procedures previously described were used toprepare samples for further screening. Five fractions representing theareas shown FIG. 1 and component(s) distribution shown in FIGS. 4A-4Ewere prepared. The samples were coded MM2A through MM2E to reflect theseanalytical characterizations and to designate the absence of caffeineand theobromine.

Each fraction was individually screened against the HCT-116, PC-3 andACHN cancer cell lines. The results indicated that the activity did notconcentrate to any one specific fraction. This type of result was notconsidered unusual, since the components in “active” natural productisolates can behave synergistically. In the case of the cocoaprocyanidin isolate (MM2), over twenty detectable components comprisedthe isolate. It was considered possible that the activity was related toa combination of components present in the different fractions, ratherthan the activity being related to an individual Component(s).

On the basis of these results, it was decided to combine the fractionsand repeat the assays against the same cancer cell lines. Severalfraction combinations produced cytotoxic effects against the PC-3 cancercell lines. Specifically, IC₅₀ values of 40 μg/mL each for MM2A and MM2Ecombination, and of 20 μg/mL each for M2C and MM2E combination, wereobtained. Activity was also reported against the HCT-116 and ACHN celllines, but as before, interference with the MTT indicator precludedprecise observations. Replicate experiments were repeatedly performed onthe HCT-116 and ACHN lines to improve the data. However, these resultswere inconclusive due to bacterial contamination and exhaustion of thetest sample material. FIGS. 6A-6D show the dose-response relationshipbetween combinations of the cocoa extracts and PC-3 cancer cells.

Nonetheless, from this data, it is clear that cocoa extracts, especiallycocoa polyphenols or procyanidins, have significant anti-tumor;anti-cancer or antineoplastic activity, especially with respect to humanPC-3 (prostate), HCT-116 (colon) and ACHN (renal) cancer cell lines. Inaddition, those results suggest that specific procyanidin fractions maybe responsible for the activity against the PC-3 cell line.

Example 7 Anti-cancer, Anti-tumor or Antineoplastic Activity of CocoaExtracts (Procyanidins)

To confirm the above findings and further study fraction combinations,another comprehensive screening was performed.

All prepared materials and procedures were identical to those reportedabove, except that the standard 4-replicates per test dose was increasedto 8 or 12-replicates per test dose. For this study, individual andcombinations of five cocoa procyanidin fractions were screened againstthe following cancer cell lines.

-   -   PC-3 Prostate    -   KB Nasopharyngeal/HeLa    -   HCT-116 Colon    -   ACHN Renal    -   MCF-7 Breast    -   SK-5 Melanoma    -   A-549 Lung    -   CCRF-CEM T-cell leukemia

Individual screenings consisted of assaying different dose levels(0.01-100 μg/mL) of fractions A, B, C, D, and E (See FIGS. 4A-4E anddiscussion thereof, supra) against each cell line. Combinationscreenings consisted of combining equal dose levels of fractions A+B,A+C, A+D, A+E, B+C, B+D, B+E, C+D, C+E, and D+E against each cell line.The results from these assays are individually discussed, followed by anoverall summary.

A. PC-3 Prostate Cell Line

FIGS. 7A-7H show the typical dose response relationship between cocoaprocyanidin fractions and the PC-3 cell line. FIGS. 7D and 7Edemonstrate that fractions D and E were active at an IC₅₀ value of 75μg/mL. The IC₅₀ values that were obtained from dose-response curves ofthe other procyanidin fraction combinations ranged between 60-80 μg/mLwhen fractions D or E were present. The individual IC₅₀ values arelisted in Table 6.

B. KB Nasopharyngeal/HeLa Cell Line

FIGS. 8A-8H show the typical dose response relationship between cocoaprocyanidin fractions and the KB Nasopharyngeal/HeLa cell line. FIGS. 8Dand 8E demonstrate that fractions D and E were active at an IC₅₀ valueof 75 μg/mL. FIGS. 8F-8H depict representative results obtained from thefraction combination study. In this case, procyanidin fractioncombination A+B had no effect, whereas fraction combinations B+E and D+Ewere active at an IC₅₀ value of 60 μg/mL. The IC₅₀ values that wereobtained from other dose response curves from other fractioncombinations ranged from 60-80 μg/mL when fractions D or E were present.The individual IC₅₀ values are listed in Table 6. These results wereessentially the same as those obtained against the PC-3 cell line.

C. HCT-116 Colon Cell Line

FIG. 9A-9H show the typical dose response relationships between cocoaprocyanidin fractions and the HCT-116 colon cell line. FIGS. 9D and 9Edemonstrate that fraction E was active at an IC₅₀ value of approximately400 μg/mL. This value was obtained by extrapolation of the existingcurve. Note that the slope of the dose response curve for fraction Dalso indicated activity. However, no IC₅₀ Value was determined from thisplot, since the slope of the curve was too shallow to obtain a reliablevalue. FIGS. 9F-9H depict representative results obtained from thefraction combination study. In this case, procyanidin fractioncombination B+D did not show appreciable activity, whereas fractioncombinations A+E and D+E were active at IC₅₀ values of 500 μg/mL and 85μg/mL, respectively. The IC₅₀ values that were obtained from doseresponse curves of other fraction combinations averaged about 250 μg/mLwhen fraction E was present. The extrapolated IC₅₀ values are listed inTable 6.

D. ACHN Renal Cell Line

FIG. 10A-10H show the typical dose response relationships between cocoaprocyanidin fractions and the ACHN renal cell line. FIGS. 10A-10Eindicated that no individual fraction was active against this cell line.FIGS. 10F-10H depict representative results obtained from the fractioncombination study. In this case, procyanidin fraction combination B+Cwas inactive, whereas the fraction combination A+E resulted in anextrapolated IC₅₀ value of approximately 500 μg/mL. Dose response curvessimilar to the C+D combination were considered inactive, since theirslopes were too shallow. Extrapolated IC₅₀ values for other fractioncombinations are listed in Table 6.

E. A-549 Lung Cell Line

FIGS. 11A-11H show the typical dose response relationships between cocoaprocyanidin fractions and the A-549 lung cell line. No activity could bedetected from any individual fraction or combination of fractions at thedoses used in the assay. However, procyanidin fractions may nonethelesshave utility with respect to this cell line.

F. SK-5 Melanoma Cell Line

FIG. 12A-12H show the typical dose response relationships between cocoaprocyanidin fractions and the SK-5 melanoma cell line. No activity couldbe detected from any individual fraction or combination of fractions atthe doses used in the assay. However, procyanidin fractions maynonetheless have utility with respect to this cell line.

G. MCF-7 Breast Cell Line

FIGS. 13A-13H show the typical dose response relationships between cocoaprocyanidin fractions and the MCF-7 breast cell line. No activity couldbe detected from any individual fraction or combination of fractions atthe doses used in the assay. However, procyanidin fractions maynonetheless have utility with respect to this cell line.

H. CCRF-CEM T-Cell Leukemia Line

Atypical dose response curves were originally Obtained against theCCRF-CEM T-cell leukemia line. However, microscopic counts of cellnumber versus time at different fraction concentrations indicated that500 μg of fractions A, B and D effected an 80% growth reduction over afour day period. A representative dose response relationship is shown inFIG. 14.

I. Summary

The IC₅₀ values obtained from these assays are collectively listed inTable 6 for all the cell lines except for CCRF-CEM T-cell leukemia. TheT-cell leukemia data was intentionally omitted from the Table, since adifferent assay procedure was used. A general summary of these resultsindicated that the most activity was associated with fractions D and E.These fractions were most active against the PC-3 (prostate) and KB(nasopharyngeal/HeLa) cell lines. These fractions also evidencedactivity against the HCT-116 (colon) and ACHN (renal) cell lines, albeitbut only at much higher doses. No activity was detected against theMCF-7 (breast), SK-5 (melanoma) and A-549 (lung) cell lines. However,procyanidin fractions may nonetheless have utility with respect to thesecell lines. Activity was also shown against the CCRF-CEM (T-cellleukemia) cell line. It should also be noted that fractions D and E arethe most complex compositionally. Nonetheless, from this data it isclear that cocoa extracts, especially cocoa procyanidins, havesignificant anti-tumor, anti-cancer or antineoplastic activity.

TABLE 6 IC₅₀ Values for Cocoa Procyanidin Fractions Against Various CellLines (IC₅₀ values in μg/mL) A- FRACTION PC-3 KB HCT-116 ACHN MCF-7 SK-5549 A B C D 90 80 E 75 75 400 A + B A + C 125 100 A + D 75 75 A + E 8075 500 500 B + C B + D 75 80 B + E 60 65 200 C + D 80 75 1000 C + E 8070 250 D + E 80 60 85 Values above 100 μg/mL were extrapolated from doseresponse curves

Example 8 Anti-Cancer, Anti-tumor or Antineoplastic Activity of CocoaExtracts (Procyanidins)

Several additional in vitro assay procedures were used to complement andextend the results presented in Examples 6 and 7.

Method A. Crystal Violet Staining Assay

All human tumor cell lines were obtained from the American Type Culturecollection. Cells were grown as monolayers in IMEM containing 10% fetalbovine serum without antibiotics. The cells were maintained in ahumidified, 5% CO₂ atmosphere at 37° C.

After trypsinization, the cells were counted and adjusted to aconcentration of 1,000-2,000 cells per 100 μL. Cell proliferation wasdetermined by plating the cells (1,000-2,000 cells/well) in a 96 wellmicrotiter plate. After addition of 100 μL cells per well, the cellswere allowed to attach for 24 hours. At the end of the 24 hour period,various cocoa fractions were added at different concentrations to obtaindose response results. The cocoa fractions were dissolved in media at a2 fold concentration and 100 μL of each solution was added in triplicatewells. On consecutive days, the plates were stained with 50 μL crystalviolet (2.5 g crystal violet dissolved in 125 mL methanol, 375 mLwater), for 15 min. The stain was removed and the plate was gentlyimmersed into cold water to remove excess stain. The washings wererepeated two more times, and the plates allowed to dry. The remainingstain was solubilized by adding 100 μL of 0.1 M sodium citrate/50%ethanol to each well. After solubilization, the number of cells werequantitated on an ELISA plate reader at 540 nm (reference filter at 410nm). The results from the ELISA reader were graphed with absorbance onthe y-axis and days growth on the x-axis.

Method B. Soft Agar Cloning Assay

Cells were cloned in soft agar according to the method described byNawata et al. (1981). Single cell suspensions were made in mediacontaining 0.8% agar with various concentrations of cocoa fractions. Thesuspensions were aliquoted into 35 mm dishes coated with mediacontaining 1.0% agar. After 10 days incubation, the number of coloniesgreater than 60 μm in diameter were determined on an Ominicron 3600Image Analysis System. The results were plotted with number of colonieson the y-axis and the concentrations of a cocoa fraction on the x-axis.

Method C. XTT-microculture Tetrazolium Assay

The XTT assay procedure described by Scudiero et al. (1988) was used toscreen various cocoa fractions. The XTT assay was essentially the sameas that described using the MTT procedure (Example 6) except for thefollowing modifications. XTT((2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H-tetrazoliumhydroxide) was prepared at 1 mg/mL medium without serum, prewarmed to37° C. PMS was prepared at 5 mM PBS. XTT and PMS were mixed together; 10μL of PMs per mL XTT and 50 μL PMS-XTT were added to each well. After anincubation at 37° C. for 4 hr, the plates were mixed 30 min. on amechanical shaker and the absorbance measured at 450-600 nm. The resultswere plotted with the absorbance on the y-axis and days growth orconcentration on the x-axis.

For methods A and C, the results were also plotted as the percentcontrol as the y-axis and days growth or concentration on the x-axis.

A comparison of the XTT and Crystal Violet Assay procedures was madewith cocoa fraction D & E (Example 3B) against the breast cancer cellline MCF-7 p168 to determine which assay was most sensitive. As shown inFIG. 15A, both assays showed the same dose-response effects forconcentrations >75 μg/mL. At concentrations below this value, thecrystal violet assay showed higher standard deviations than the XTTassay results. However, since the crystal violet assay was easier touse, all subsequent assays, unless otherwise specified, were performedby this procedure.

Crystal violet assay results are presented (FIGS. 15B-15E) todemonstrate the effect of a crude polyphenol extract (Example 2) on thebreast cancer cell line MDA MB231, prostate cancer cell line PC-3,breast cancer cell line MCF-7 p163, and cervical cancer cell line Hela,respectively. In all cases a dose of 250 μg/mL completely inhibited allcancer cell growth over a period of 5-7 days. The Hela cell lineappeared to be more sensitive to the extract, since a 100 μg/mL dosealso inhibited growth. Cocoa fractions from Example 3B were also assayedagainst Hela and another breast cancer cell line SKBR-3. The results(FIGS. 15F and 15G) showed that fraction D & E has the highest activity.As shown in FIGS. 15H and 15I, IC₅₀ values of about 40 μg/mL D & E wereobtained from both cancer cell lines.

The cocoa fraction D & E was also tested in the soft agar cloning assaywhich determines the ability of a test compound(s) to inhibit anchorageindependent growth. As shown in FIG. 15J, a concentration of 100 μg/mLcompletely inhibited colony formation of Hela cells.

Crude polyphenol extracts obtained from eight different cocoa genotypesrepresenting the three horticultural races of cocoa were also assayedagainst the Hela cell line. As shown in FIG. 15K all cocoa varietiesshowed similar dose-response effects. The UIT-1 variety exhibited themost activity against the Hela cell line. These results demonstratedthat all cocoa genotypes possess a polyphenol fraction that elicitsactivity against at least one human cancer cell line that is independentof geographical origin, horticultural race, and genotype.

Another series of assays were performed on crude polyphenol extractsprepared on a daily basis from a one ton scale traditional 5-dayfermentation of Brazilian cocoa beans, followed by a 4-day sun dryingstage. The results shown in FIG. 15L showed no obvious effect of theseearly processing stages, suggesting little change in the composition ofthe polyphenols. However, it is known (Lehrian and Patterson, 1983) thatpolyphenol oxidase (PPO) will oxidize polyphenols during thefermentation stage. To de termine what effect enzymically oxidizedpolyphenols would have on activity, another experiment was performed.Crude PPO was prepared by extracting finely ground, unfermented, freezedried, defatted Brazilian cocoa beans with acetone at a ratio of 1 gmpowder to 10 mL acetone. The slurry was centrifuged at 3,000 rpm for 15min. This was repeated three times, discarding the supernatant each timewith the fourth extraction being poured through a Buchner filteringfunnel. The acetone powder was allowed to air dry, followed by assayaccording to the procedures described by McLord and Kilara, (1983). To asolution of crude polyphenols (100 mg/10 mL Citrate-Phosphate buffer,0.02M, pH 5.5) 100 mg of acetone powder (4,000 μ/mg protein) was addedand allowed to stir for 30 min. with a stream of air bubbled through theslurry. The sample was centrifuged, at 5,000×g for 15 min. and thesupernatant extracted 3× with 20 mL ethyl acetate. The ethyl acetateextracts were combined, taken to dryness by distillation under partialvacuum and 5 mL water added, followed by lyophilization. The materialwas then assayed against Hela cells and the dose-response compared tocrude polyphenol extracts that were not enzymically treated. The results(FIG. 15M) showed a significant shift in the dose-response curve for theenzymically oxidized extract, showing that the oxidized products weremore inhibitory than their native forms.

Example 9 Antioxidant Activity of Cocoa Extracts Containing Procyanidins

Evidence in the literature suggests a relationship between theconsumption of naturally occurring antioxidants (Vitamins C, E andB-carotene) and a lowered incidence of disease, including cancer(Designing Foods, 1993; Caragay, 1992). It is generally thought thatthese antioxidants affect certain oxidative and free radical processesinvolved with some types of tumor promotion. Additionally, some plantpolyphenolic compounds that have been shown to be anticarcinogenic, alsopossess substantial antioxidant activity (Ho et al., 1992; Huang et al.,1992).

To determine whether cocoa extracts containing procyanidins possessedantioxidant properties, a standard Rancimat method was employed. Theprocedures described in Examples 1, 2 and 3 were used to prepare cocoaextracts which were manipulated further to produce two fractions fromgel permeation chromatography. These two fractions are actually combinedfractions A through C, and D and E (See FIG. 1) whose antioxidantproperties were compared against the synthetic antioxidants BHA and BHT.

Peanut Oil was pressed from unroasted peanuts after the skins wereremoved. Each test compound was spiked into the oil at two levels, ˜100ppm and ˜20 ppm, with the actual levels given in Table 7. 50 μL ofmethanol solubilized antioxidant was added to each sample to aid indispersion of the antioxidant. A control sample was prepared with 50 μLof methanol containing no antioxidant.

The samples were evaluated in duplicate, for oxidative stability usingthe Rancimat stability test at 100° C. and 20 cc/min of air.Experimental parameters were chosen to match those used with the ActiveOxygen Method (AOM) or Swift Stability Test (Van Oosten et al., 1981). Atypical Rancimat trace is shown in FIG. 16. Results are reported inTable 8 as hours required to reach a peroxide level of 100 meq.

TABLE 7 Concentrations of Antioxidants LEVEL 1 LEVEL 2 SAMPLE ppmButylated Hydroxytoluene (BHT) 24 120 Butylated Hydroxyanisole (BHA) 24120 Crude Ethyl Acetate Fraction of Cocoa 22 110 Fraction A-C 20 100Fraction D-E 20 100

TABLE 8 Oxidative Stability of Peanut Oil with Various Antioxidants 20ppm 100 ppm SAMPLE average Control 10.5 ± 0.7 BHT 16.5 ± 2.1 12.5 ± 2.1BHA 13.5 ± 2.1 14.0 ± 1.4 Crude Cocoa Fraction 18.0 ± 0.0 19.0 ± 1.4Fraction A-C 16.0 ± 6.4 17.5 ± 0.0 Fraction D-E 14.0 ± 1.4 12.5 ± 0.7

These results demonstrated increased oxidative stability of peanut oilwith all of the additives tested. The highest increase in oxidativestability was realized by the sample spiked with the crude ethyl acetateextract of cocoa. These results demonstrated that cocoa extractscontaining procyanidins have antioxidant potential equal to or greaterthan equal amounts of synthetic BHA and BHT. Accordingly, the inventionmay be employed in place of BHT or BHA in known utilities of BHA or BHT,such as for instance as an antioxidant and/or food additive. And, inthis regard, it is noted too that the invention is from an ediblesource. Given these results, the skilled artisan can also readilydetermine a suitable amount of the invention to employ in such “BHA orBHT” utilities, e.g., the quantity to add to food, without undueexperimentation.

Example 10 Topoisomerase II Inhibition Study

DNA topoisomerase I and II are enzymes that catalyze the breaking andrejoining of DNA strands, thereby controlling the topological states ofDNA (Wang, 1985). In addition to the study of the intracellular functionof topoisomerase, one of the most significant findings has been theidentification of topoisomerase II as the primary cellular target for anumber of clinically important antitumor compounds (Yamashita et al.,1990) which include intercalating agents (m-AMSA, Adriamycin® andellipticine) as well as nonintercalating epipodophyllotoxins. Severallines of evidence indicate that some antitumor drugs have the commonproperty of stabilizing the DNA—topoisomerase II complex (“cleavablecomplex”) which upon exposure to denaturing agents results in theinduction of DNA cleavage (Muller et al., 1989). It has been suggestedthat the cleavable complex formation by antitumor drugs produces bulkyDNA adducts that can lead to cell death.

According to this attractive model, a specific new inducer of DNAtopoisomerase II cleavable complex is useful as an anti-cancer,anti-tumor or antineoplastic agent. In an attempt to identify cytotoxiccompounds with activities that target DNA, the cocoa procyanidins werescreened for enhanced cytotoxic activity against several DNA—damagesensitive cell lines and enzyme assay with human topoisomerase IIobtained from lymphoma.

A. Decatenation of Kinetoplast DNA by Topoisomerase II

The in vitro inhibition of topoisomerase II decatenation of kinetoplastDNA, as described by Muller et al. (1989), was performed as follows.Nuclear extracts containing topoisomerase II activity were prepared fromhuman lymphoma by modifications of the methods of Miller et al. (1981)and Danks et al. (1988). One unit of purified enzyme was enough todecatenate 0.25 μg of kinetoplast DNA in 30 min. at 34° C. KinetoplastDNA was obtained from the trypanosome Crithidia fasciculata. Eachreaction was carried out in a 0.5 mL microcentrifuge tube containing19.5 μL H₂O, 2.5 μL 10× buffer (1× buffer contains 50 mM tris-HCl, pH8.0, 120 mM KCl, 10 mM MgCl₂, 0.5 mM ATP, 0.5 mM dithiothreitol and 30μg BSA/mL), 1 μL kinetoplast DNA (0.2 μg), and 1 μL DMSO-containingcocoa procyanidin test fractions at various concentrations. Thiscombination was mixed thoroughly and kept on ice. One unit oftopoisomerase was added immediately before incubation in a waterbath at34° C. for 30 min.

Following incubation, the decatenation assay was stopped by the additionof 5 μL stop buffer (5% sarkosyl, 0.0025% bromophenol blue, 25%glycerol) and placed on ice. DNA was electrophoresed on a 1% agarose gelin TAE buffer containing ethidium bromide (0.5 μg/mL). Ultravioletillumination at 310 nm wavelength allowed the visualization of DNA. Thegels were photographed using a Polaroid Land camera.

FIG. 17 shows the results of these experiments. Fully catenatedkinetoplast DNA does not migrate into a 1% agarose gel. Decatenation ofkinetoplast DNA by topoisomerase II generates bands of monomeric DNA(monomer circle, forms I and II) which do migrate into the gel.Inhibition of the enzyme by addition of cocoa procyanidins is apparentby the progressive disappearance of the monomer bands as a function ofincreasing concentration. Based on these results, cocoa procyanidinfractions A, B, D, and E were shown to inhibit topoisomerase II atconcentrations ranging from 0.5 to 5.0 μg/mL. These inhibitorconcentrations were very similar to those obtained for mitoxanthrone andm-AMSA [4′-(9-acridinylamino)methanesulfon-m-anisidide].

B. Drug Sensitive Cell Lines

Cocoa procyanidins were screened for cytotoxicity against severalDNA-damage sensitive cell lines. One of the cell lines was the xrs-6 DNAdouble strand break repair mutant developed by P. Jeggo (Kemp et al.,1984). The DNA repair deficiency of the xrs-6 cell line renders themparticularly sensitive to x-irradiation, to compounds that produce DNAdouble strand breaks directly, such as bleomycin, and to compounds thatinhibit topoisomerase II, and thus may indirectly induce double strandbreaks as suggested by Warters et al. (1991). The cytotoxicity towardthe repair deficient line was compared to the cytotoxicity against a DNArepair proficient CHO line, BR1. Enhanced cytotoxicity towards therepair deficient (xrs-6) line was interpreted as evidence for DNAcleavable double strand break formation.

The DNA repair competent CHO line, BR1, was developed by Barrows et al.(1987) and expresses 06-alkylguanine-DNA-alkyltransferase in addition tonormal CHO DNA repair enzymes. The CHO double strand break repairdeficient line (xrs-6) was a generous gift from Dr. P. Jeggo andco-workers (Jeggo et al., 1989). Both of these lines were grown asmonolayers in alpha-MEM containing serum and antibiotics as described inExample 6. Cells were maintained at 37° C. in a humidified 5% CO₂atmosphere. Before treatment with cocoa procyanidins, cells grown asmonolayers were detached with trypsin treatment. Assays were performedusing the MTT assay procedure described in Example 6.

The results (FIG. 18) indicated no enhanced cytotoxicity towards thexrs-6 tells suggesting that the cocoa procyanidins inhibitedtopoisomerase II in a manner different from cleavable double strandbreak formation. That is, the cocoa procyanidins interact withtopoisomerase II before it has interacted with the DNA to form anoncleavable complex.

Noncleavable complex forming compounds are relatively new discoveries.Members of the anthracyclines, podophyllin alkaloids, anthracenediones,acridines, and ellipticines are all approved for clinical anti-cancer,anti-tumor or antineoplastic use, and they produce cleavable complexes(Liu, 1989). Several new classes of topoisomerase II inhibitors haverecently been identified which do not appear to produce cleavablecomplexes. These include amonafide (Hsiang et al., 1989), distamycin(Fesen et al., 1989), flavanoids (Yamashita et al., 1990), saintopin(Yamashita et al., 1991), membranone (Drake et al., 1989), terpenoids(Kawada et al., 1991), anthrapyrazoles (Fry et al., 1985),dioxopiperazines (Tanabe et al., 1991), and the marine acridine-dercitin(Burres et al., 1989).

Since the cocoa procyanidins inactivate topoisomerase II beforecleavable complexes are formed, they have chemotherapy value eitheralone or in combination with other known and mechanistically definedtopoisomerase II inhibitors. Additionally, cocoa procyanidins alsoappear to be a novel class of topoisomerase II inhibitors, (Kashiwada etal., 1993) and may thus be less toxic to cells than other knowninhibitors, thereby enhancing their utility in chemotherapy.

The human breast cancer cell line MCF-7 (ADR) which expresses a membranebound glycoprotein (gp170) to confer multi-drug resistance (Leonessa etal., 1994) and its parental line MCF-7 p168 were used to assay theeffects of cocoa fraction D & E. As shown in FIG. 19, the parental linewas inhibited at increasing dose levels of fraction D & E, whereas theAdriamycin (ADR) resistant line was less effected at the higher doses.These results show that cocoa fraction D & E has an effect on multi-drugresistant cell lines.

Example 11 Synthesis of Procyanidins

The synthesis of procyanidins was performed according to the proceduresdeveloped by Delcour et al. (1983), with modification. In addition tocondensing (+)-catechin with dihydroquercetin under reducing conditions,(−)-epicatechin was also used to reflect the high concentrations of(−)-epicatechin that naturally occur in unfermented cocoa beans. Thesynthesis products were isolated, purified, analyzed, and identified bythe procedures described in Examples 3, 4 and 5. In this manner, thebiflavanoids, triflavanoids and tetraflavanoids are prepared and used asanalytical standards and, in the manner described above with respect tococoa extracts.

Example 12 Assay of Normal Phase Semi-preparative Fractions

Since the polyphenol extracts are compositionally complex, it wasnecessary to determine which components were active against cancer celllines for further purification, dose-response assays and comprehensivestructural identification. A normal phase semi preparative HPLCseparation (Example 3B) was used to separate cocoa procyanidins on thebasis of oligomeric size. In addition to the original extract, twelvefractions were prepared (FIGS. 2B and 15 O) and assayed at 100 μg/mL and25 μg/mL doses against Hela to determine which oligomer possessed thegreatest activity. As shown in FIG. 20, fractions 4-11(pentamer-dodecamer) demonstrated IC₅₀ values of approximately 25 μg/mL.These results indicated that these specific oligomers had the greatestactivity against Hela cells. Additionally, normal phase HPLC analysis ofcocoa fraction D & E indicated that this fraction was enriched withthese oligomers.

From the foregoing, it is clear that the extract and cocoa polyphenols,as well as the compositions method and kit, of the invention haveutility. In this regard, it is mentioned that the invention is from anedible source and, that the activity in vitro can demonstrate at leastsome activity in vivo, especially considering the doses discussed above.

Additionally, the above description shows that the extract and cocoapolyphenols, as well as the compositions, method and kit haveantioxidant activity like that of BHT and BHA, as well as oxidativestability. Thus, the invention can be employed in place of BHT or BHA inknown utilities of BHA and BHT, such as an antioxidant, for instance, anantioxidant food additive. The invention can also be employed in placeof topoisomerase-inhibitors in the presently known utilities therefor.Accordingly, there are many compositions and methods envisioned by theinvention; for instance, antioxidant or preservative compositions,topoisomerase-inhibiting compositions, methods for preserving food orany desired item such as from oxidation, and methods for inhibitingtopoisomerase which comprise either the extract and/or cocoapolyphenol(s) or which comprise contacting the food, item ortopoisomerase with the respective composition or with the extract and/orcocoa polyphenol(s).

Having thus described in detail the preferred embodiments of the presentinvention, it is to be understood that the invention defined by theappended claims is not to be limited by particular details set forth inthe above descriptions as many apparent variations thereof are possiblewithout departing from the spirit or scope of the present invention.

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1. A substantially pure cocoa extract comprising cocoa polyphenolsincluding cocoa procyanidins, which extract is prepared by a processcomprising the steps of: (a) reducing cocoa beans to a cocoa powder, (b)defatting the cocoa powder, (c) extracting the cocoa polyphenol(s) fromthe defatted cocoa powder, and (d) purifying the extracted cocoapolyphenols.
 2. The cocoa extract of claim 1, wherein the process ofreducing the cocoa beans to the cocoa powder comprises the steps of:freeze drying the cocoa beans and pulp, depulping the freeze dried massof cocoa beans and pulp, dehulling the depulped, freeze-dried cocoabeans, and grinding the dehulled cocoa beans.
 3. The cocoa extract ofclaim 1, wherein the cocoa extract is purified by gel permeationchromatography and/or by preparative high performance liquidchromatography (HPLC).
 4. The cocoa extract of claim 2, wherein thecocoa extract is purified by gel permeation chromatography and/or bypreparative high performance liquid chromatography (HPLC).
 5. The cocoaextract of claim 1, wherein the cocoa procyanidins include(−)-epicatechin, (+)-catechin and dimers through dodecamers.
 6. Thecocoa extract of claim 2 or 3, wherein the cocoa procyanidins include(−)-epicatechin, (+)-catechin, and dimers through dodecamers.
 7. Thecocoa extract of claim 5, wherein the dimers are procyanidin B-2,procyanidin B-5, and procyanidin A-2 and wherein the trimer isprocyanidin C-1.
 8. The cocoa extract of claim 6, wherein the dimers areprocyanidin B-2, procyanidin B-5, and procyanidin A-2 and wherein thetrimer is procyanidin C-1.